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Hands-on Lab·LPIC-2

The initramfs, the bootloader, and the rescue targets

Topic 202 is weight 9 and covers recovery, the initramfs and bootloaders. This guide reads what GRUB generated and what the kernel was actually told, opens the initramfs to count what is inside it, rebuilds one safely to a temporary file, compares the two families' boot layouts, and clears a machine that was genuinely reporting itself degraded.

201: System Startup Guide 25 of 29 Intermediate

Both families, because the boot layout is where they differ most: different directories, different entry formats, and a different tool for building the initramfs.
Server NameIP AddressOSRolesCPURAMHDD
LPIC2-A01192.168.0.78Ubuntu 26.04 LTSPrimary service host - BIND, Apache, Samba, Postfix. Topic 204 RAID runs on loop devices; this machine has no spare disk2 Core4 GB50 GB
LPIC2-B01192.168.0.79AlmaLinux 10.2Second service host - nginx, NFS, DNS secondary, and the other family's spelling of each service2 Core4 GB50 GB

This guide includes

Use this before you need it - the day a machine does not boot is the wrong time to learn where its bootloader configuration lives. This matters because the file you edit is not the file that boots, and because a machine can run perfectly while reporting itself degraded over units whose packages were removed months ago.

Before you start

  1. Which bootloader, and where it keeps its mind

  2. What the kernel was actually told

  3. Inside the initramfs

  4. Building one, without touching the one that boots

  5. The targets you boot into when something is broken

  6. A machine that reports itself degraded

  7. The same boot directory, two layouts

  8. Putting the machine back

Official sources

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